Humidification system and method for a mobile platform

ABSTRACT

A humidification system and method particularly well adapted for use in commercial aircraft to provide substantially micro-organism free humidified air within a passenger cabin of the aircraft. The system employs a vessel for holding a quantity of water therein. The vessel is disposed within a microwave oven which is used to heat the water within the vessel to the boiling point such that steam is generated therefrom. This steam is directed into an airflow duct and used to humidify an airflow being supplied into a cabin area of the aircraft. The steam is substantially micro-organism free. A controller is used to cycle the filling and draining of the vessel to achieve a desired humidity level for the airflow. Optimally, a vacuum accumulator is employed to assist in rapid draining of the water from the vessel.

FIELD OF THE INVENTION

The present invention relates to humidification systems, and moreparticularly to a humidification system and method which removesmicro-organisms and mineral deposits from water being used in the systemto provide even cleaner humidified air within a confined area.

BACKGROUND OF THE INVENTION

Humidification systems are used in buildings and mobile platforms suchas aircraft, and other moving platforms, to humidify the air within aconfined area in which occupants or passengers are residing. Thehumidification of the air can significantly add to the comfort ofoccupants or passengers.

One drawback with presently utilized humidification systems is that mostsuffer from relatively high maintenance, in addition to accumulations ofmineral deposits from the water, the growth/transmittal ofmicro-organisms from the water used, relatively high noise, or acombination of these problems. In relatively small, predefined areas,such as within a passenger cabin area of an aircraft, where the aircraftis pressurized and the only airflow through the cabin is the humidifiedair flow, the need to remove micro-organisms and present a substantiallybacteria-free airflow is particularly important. In aircraftapplications, the added maintenance required because of the accumulationof mineral deposits in various components of the system is furtherhighly undesirable because such maintenance action adds additional costto an airline operating the aircraft.

In view of the foregoing, it would be highly desirable to provide ahumidification system that is especially well suited for use on mobileplatforms such as aircraft, busses, trains, ships, etc. that does notsuffer from the traditional high maintenance associated with previouslydeveloped humidification systems. It would also be highly desirable toprovide a humidification system which is capable of destroyingmicro-organisms from water being used in the system to thus provide abacteria-free, humidified airflow to passengers, occupants and/or crewmembers on a mobile platform. It would further be highly desirable toprovide such a humidification system which does not add significantadditional cost, does not require significant additional maintenance anddoes not take up appreciable space on board the mobile platform.

SUMMARY OF THE INVENTION

The present invention is directed to an apparatus and method forproviding even cleaner humidified area within a pre-defined area of aroom or confined area of a mobile platform. In one preferred embodimentthe present invention includes a vessel for receiving a quantity ofwater. The vessel is disposed within an oven and further includes anoutflow conduit for steam vapor generated within the vessel when it isheated, and a water outflow conduit for allowing water to be drainedfrom the vessel. The steam outflow conduit is directed into an airflowconduit carrying an airflow to a room or other area. In one preferredform the humidification system of the present invention is adapted foruse with a commercial aircraft although it will be appreciated that thepresent invention can be used to help humidify a room within a fixedstructure or an area within any other type of mobile platform such as abus, train, ship, etc.

A controller is used for controlling the admittance of fresh water intothe vessel as well as the draining of water from the vessel. Optimally,but preferably, an overflow drain is coupled to the vessel to drain anywater in the vessel that rises above a predetermined upper level duringa heating cycle.

In operation, the water inside the vessel is heated by the oven togenerate steam. Advantageously, the energy generated by the oven killsall or substantially all of the micro-organisms in the water. As aresult, the steam generated during this heating operation is at leastsubstantially micro-organism free. The steam is routed through the vaporoutflow conduit into the airflow conduit where it becomes entrained inthe airflow being directed into the room or other confined area. In onepreferred embodiment an injection valve is utilized to help betterdisperse the steam vapor within the airflow. After each heating cycle iscompleted, the quantity of water within the vessel is drained by thecontroller opening the valve in the water outflow conduit.

In another preferred embodiment specifically well adapted for use on ahigh speed moving platform such as a commercial aircraft, a vacuumaccumulator is incorporated for helping to assist in draining the waterfrom the vessel. The vacuum accumulator has an input which is incommunication with an output of the water outflow conduit. The vacuumaccumulator also has an output which is in communication with a drainmast of the aircraft. After each heating cycle, the quantity of waterwithin the vessel is drained therefrom into the vacuum accumulator. Avacuum being exerted at the drain mast by the high speed movement of theaircraft generates a vacuum within the accumulator. This vacuum furtherhelps in drawing the water out from the vessel, through the accumulator,and out through the drain mast into the ambient environment.

The various preferred embodiments enable a substantially micro-organismfree humidified airflow to be provided to a room or cabin area of amobile platform. The rapid draining away of water after the heatingcycle further helps to significantly reduce the build up of mineraldeposits within the vessel and other components of the system. As aresult, the humidification system of the present invention reduces theneed for periodic maintenance thereof which in turn can contribute to areduction in the cost of operating the humidification system.

Further areas of applicability of the present invention will becomeapparent from the detailed description provided hereinafter. It shouldbe understood that the detailed description and specific examples areintended for purposes of illustration only and are not intended to limitthe scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1 is a diagram of a humidification system in accordance with apreferred embodiment of the present invention disposed within thefuselage of an aircraft; and

FIG. 2 is an end view of the injection nozzle used with thehumidification system of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following description of the preferred embodiment(s) is merelyexemplary in nature and is in no way intended to limit the invention,its application, or uses.

Referring to FIG. 1, there is shown a humidification system 10 inaccordance with a preferred embodiment of the present invention. Thehumidification system 10 can be used within fixed structures to providean especially clean, mineral and micro-organism free, humidified airflowwithin a confined area, such as a room, of the structure, oralternatively it can be used within a mobile platform such as anaircraft, bus, train, ship or other moving structure. While thefollowing description will describe the system 10 as being used with anaircraft, it will be appreciated that the system can be employed in avariety of applications and is therefore not limited to only thoseinvolving aircraft.

The system generally includes a vessel 12 for containing a predeterminedquantity of water therein, a microwave oven 14 within which the vesselis disposed for heating the water within the vessel 12, and a controller16 for controlling operation of the system 10. The controller 16controls the admittance of fresh water into the vessel 12 through awater supply conduit 18 by controllably opening and closing a valve 20disposed in the water supply conduit. The water flowing through thewater supply conduit 18 is supplied from a suitable potable waterreservoir 22. A water level sensor 23 monitored by the controller 16 isused to monitor the level of water within the vessel 12 during a fillcycle when the vessel 12 is filled. The water supply conduit 18 has anoutput end 24 through which water may be drained or pumped into thevessel 12 to fill the vessel. The vessel 12 may be a ceramic vessel ormay be made from any suitable material that is able to withstandrepeated heating and cooling cycles.

The system 10 further includes a steam or vapor outflow conduit 26 whichis in communication with an upper end 12 a of the vessel 12 to receivesteam generated as the water is heated within the vessel 12. A pressureregulator valve 25 is disposed within the outflow conduit 26 andcontrolled by the controller 16. The vapor flows through the conduit 26,through the pressure regulator valve 25 and into air flowing through anairflow conduit 28. The water vapor is intermixed with the airflow andeventually is directed into a cabin area of an aircraft 30.

The system 10 further preferably comprises a water overflow, pressurerelief conduit 32 which is also in communication with the vessel 12. Apressure regulator valve 34 controlled by controller 16 is disposed inthe overflow/pressure relief conduit 32, and is selected such that itopens when a predetermined over pressure is reached in the conduit 32 oran overflow condition occurs in the conduit 32. The controller is alsoable to control this valve in the event of any condition whereinimmediate opening or closing of this valve is required. Sensing of afluid overflow condition is accomplished by a sensor 32 a placedadjacent to the level of an overflow port 32 b in the vessel thatcommunicates with conduit 32. Thus, if the pressure within the vessel 12exceeds a predetermined upper limit, then pressure within the vessel 12may be alleviated by the overflow/pressure relief valve 34 opening anddraining a subquantity of water from the vessel 12. Similar logic isused for sensing an overflow condition of vessel 12.

The system 10 further includes a drain or outflow conduit 36 which is incommunication with a lower end 37 of the vessel 12. The drain conduit 36includes a valve 38 disposed therein which is controlled by thecontroller 16. When the drain valve 38 is opened, water within thevessel 12 may be drained through the conduit 36 and a fresh quantity ofwater admitted into the vessel 12.

Referring further to FIG. 1, an optional vacuum accumulator 40 isincluded for assisting in the draining of water from the vessel 12. Thevacuum accumulator 40 includes an input 42 which is in communicationwith an outlet end 44 of the drain conduit 36. The vacuum accumulator 40further includes an outflow port 46 which is coupled to a drain mast 48of the aircraft 30. An output port 50 of the drain mast 48 is incommunication with the ambient environment outside the aircraft 30. Thedrain mast 48 includes a one way, vacuum actuated pressure relief valve52 disposed therein. While the vacuum accumulator 40 forms an especiallyconvenient means for assisting and emptying the contents of the vessel12, it will be appreciated that the system 10 could readily be employedwithout it. For example, portion 44 of drain conduit 36 could be coupleddirectly to the drain mast 50 to allow draining of fluid from the vessel12 directly into the drain mast 48. However, the use of the vacuumaccumulator guarantees a vacuum source will be present even whenaerodynamic conditions surrounding the drain mast 48 output port 50 donot provide favorable vacuum conditions when the vessel 12 is commandedto drain the water and minerals from the vessel 12.

The microwave oven has a power rating of preferably between about 250watts-1000 watts although it will be appreciated that a microwave ovenhaving a power rating outside this range could readily be employed. Theprincipal factor in determining the power required for the microwave isthe amount of water that needs to be heated within a given time.Assuming the vessel 12 has the capacity to hold one quart (0.95 liter)of water, and further assuming that the temperature of water suppliedfrom the reservoir 22 into the vessel 12 is approximately 50° F. (10°C.), then an oven having a power rating of preferably at least about1000 watts will be preferred to bring the water to the boiling pointwithin about fifteen minutes. Suitable microwave ovens are availablefrom various companies such as Panasonic and Sanyo. Furthermore, anysuitable type of heating system/device could be implemented, providedsame is able to heat the water in the vessel rapidly to the boilingpoint, such as for example radar energy. As such, it will be appreciatedthat the present invention is not limited to use with only a microwaveoven. However, the use of a microwave oven provides the advantage thatthe water does not need to contact any heating element, and this reducesthe possibility of any buildup of minerals on the heating component ofthe system, which many previously developed systems are susceptible to.

With further reference to FIG. 1, the controller 16 may optionallymonitor an output from a humidity sensor 54 disposed within the airflowconduit 28. If the humidity sensor 54 is employed, then a “closed loop”humidity sensing system may be formed with the controller monitoring thereal time humidity of the airflow 28 and controlling valves 20 and 38 toadjust the admittance and draining of water, respectively, so as tomaintain the humidity of the airflow 28 within a given predeterminedrange.

With further reference to FIGS. 1 and 2, an injection nozzle 56 canoptionally be employed to help better disburse the steam exiting throughthe vapor conduit 26. The injection nozzle 56 is disposed generallylongitudinally in line with the airflow flowing through the conduit 28and includes a, plurality of vanes 58. The vanes 58 are arranged in acircumferential pattern (FIG. 2) to extend from a tubular member 60 andare further arranged such that they are disposed at preferably about a15°-20° angle of attack relative to the direction of flow of the airflowing within the conduit 28. The tubular member 60 is fixedly coupledto the vapor outflow conduit 26 and includes a plurality of openings 61therein. The steam exiting from the vapor outflow conduit 26 flowsthrough the openings 61 and into the airflow conduit 28 and forms steamjets 63. The air flowing in the airflow conduit 28 encounters thestaggered steam jets 63 exiting through the openings 61 and begins tointermix therewith. Further mixing of the steam jets 63 and the airflowing in the conduit occurs as a result of the swirling actionimparted to the air/stream jet mixture by the vanes 58. Essentially, thevanes 58 help to create a swirling, turbulent, air/stream flow thatcauses thorough intermixing of the air and steam jets 63.

Turning now to the operation of the system 10, initially the controller16 opens valve 20 to admit a predetermined quantity of water into thevessel 12 from the water reservoir 22 through water inflow conduit 18.The water flows through output end 24 of the conduit 18 and fills thevessel 12 until water level sensor 23 signals to controller 16 that thewater has reached a predetermined upper level within the vessel 12. Atthis point the controller 16 closes valve 20 to interrupt the flow ofwater through the water supply conduit 18. It will also be appreciatedthat while the vessel 12 is filling, the controller 16 maintains valve38 in a closed position.

The controller 16 then causes the microwave oven 14 to be turned on tobegin heating the water within the vessel 12. The microwave oven 14heats the vessel 12 for a time sufficient to allow the water to come toa boil. This in turn generates mineral/micro-organism free steam withinthe vessel 12 which rises through the vapor outflow conduit 26. At thispoint the controller 16 turns off the microwave oven 14 for a briefperiod of time as the pressure of the steam is regulated through thevalve 25 and through the vapor outflow conduit 26, and flows through theopenings 61 in the tubular member 60. The steam jets 63 are dispersed bythe injection valve 56, that induces a swirl in the air, and that causesthe air to be thoroughly intermixed with the steam jets 63 to form theclean, humidified airflow through the vapor outflow conduit 26. Theresulting mixture forms an especially clean, mineral free humidifiedairflow. The humidified air then flows into the cabin of the aircraft30.

In a preferred implementation the pressure regulator valve 25 isselected such that remains closed until a predetermined steam pressureis reached that is preferably about 1.0 psi greater than the knownpressure in the airflow conduit 28. In this manner, the steam enteringthe airflow conduit 28 will be slightly super heated. The slightly superheated steam readily mixes with the air flowing in the airflow conduit28, thus avoiding the need for a large cone or other large rotatingstructure to ensure thorough mixing. This also avoids the problem withlarge duct pressure losses in the airflow conduit 28 that can be causedby large cones or like rotating structures that are typically used toinduce a swirl in the airflow.

After a brief predetermined time, the controller 16 shuts down themicrowave oven and opens valve 38, thus allowing the water within thevessel 12 to be drained therefrom. The water is drained very rapidly inpart by a vacuum supplied by the vacuum accumulator 40. This rapidevacuation of water from the vessel 12 helps to drain minerals in thewater and prevent the buildup of such minerals within the vessel 12. Aswill be appreciated, the boiling of the water within the vessel 12produces a generally micro-organism free vapor which allows a humidifiedairstream to be generated which is also substantially free ofmicro-organisms.

If the vacuum accumulator 40 is incorporated into the system 10, thenthe draining of water from the vessel 12 is accomplished especiallyrapidly. The vacuum accumulator, in one preferred form, comprises ametal canister, although it will be appreciated that other materialscould be used just as well provided same are structurally rigid and canwithstand the drop in pressure as a result of the vacuum generated.

As the aircraft operates, its relatively high speed of movement causes adrop in pressure at the outlet port 50 of the drain mast 48. This dropin pressure causes pressure relief valve 52 to open and air within thevacuum accumulator 40 is drawn out therefrom. Eventually the pressure onboth sides of the pressure relief valve 52 will equalize and the valvewill close. When the controller 16 determines that water needs to bedrained from the vessel 12, it opens valve 38. The pressure of the steam(i.e., vapor) generated within the vessel 12 helps to push the water outof the vessel 12 into the drain conduit 36 and through the open valve 38into the vacuum accumulator 40. At the moment valve 38 is opened bycontroller 16, the low pressure area formed within the vacuumaccumulator 40 assists in rapidly draining water out through the drainconduit 36, through the vacuum accumulator 40, through the drain mast 48and out into the ambient environment. To begin a subsequent cycle, thecontroller then closes valve 38 and opens valve 20 to admit a freshquantity of water from the water reservoir 22 into the vessel 12, andthe above-described cycle is repeated. If humidity sensor 54 isemployed, the controller 16 monitors this sensor and adjusts theabove-described cycle accordingly through the control of valves 20 and38 such that the humidity of the air flowing through the airflow conduit28 is maintained within a predetermined range.

While the vacuum accumulator 40 forms an especially convenient means forensuring that the water is drained quickly out of the vessel 12 after aheating cycle is completed, if the vacuum being experienced by the drainmast 48 is not sufficient to provide the intended vacuum, then the waterdrained from the vessel 12 will be temporarily stored within theaccumulator 40. The use of the vacuum accumulator 40 eliminates some ofthe drawbacks with previous humidification systems employed in aircraftwhere the vacuum experienced by the drain mast 40 is not alwayssufficient to assist in the draining process. Such conditions can occur,for example, when the aircraft is in a descent or a turn. During theseconditions, there may not be a sufficient vacuum created on the drainmast 48 to assist in quickly draining water from the vessel 12. As aresult, water may not be drained sufficiently quickly to permit theinitiation of a new heating cycle. The vacuum accumulator 40, however,itself forms a temporary fluid reservoir for those times when theaircraft may be in a phase of flight where sufficient vacuum is notpresent at the drain mast 48 to permit rapid draining of the water fromthe vessel 12.

The use of a microwave oven to boil the water provides a micro-organismfree, humidified airflow into the cabin area of the aircraft 30. Thisfurther serves to reduce maintenance and help to prevent thegrowth/transmittal of micro-organisms within various components of thesystem 10. These factors serve to significantly reduce maintenance costswhen operating system 10.

The system of the present invention further forms a relatively quietsystem and further provides the benefit that components thereof are notconsumed or rapidly worn out during operation, which are drawbackstypically associated with previously developed humidification systems.

The present invention further effectively eliminates minerals from thesteam that is generated from the water in the vessel. Previouslydeveloped systems that make use of an evaporating sponge or atomizationprocess allow the minerals to enter the airstream in the airflow duct.These minerals can collect and form a white powder in the duct, and betransmitted as white dust into the air of a flight deck or cabin areawhen an aircraft makes a hard landing. With the steam-based system 10 ofthe present invention, the minerals are left in the water in the boiler,rather than being transported via the steam into the air stream flowingin the flight deck or cabin.

Furthermore, the system 10 helps to reduce pressure losses in theducting used within the aircraft which can help to reduce the backpressure on an air-conditioning system employed during normal operationof the aircraft. The use of a micro-organism free humidification systemsignificantly improves the comfort of the environment within the cabinof the aircraft as well as helping to provide cleaner air for theoccupants to breathe.

While various preferred embodiments have been described, those skilledin the art will recognize modifications or variations which might bemade without departing from the inventive concept. The examplesillustrate the invention and are not intended to limit it. Therefore,the description and claims should be interpreted liberally with onlysuch limitation as is necessary in view of the pertinent prior art.

1. A humidification system for providing substantially micro-organism free water vapor into an airflow conduit flowing a quantity of air therethrough, said system comprising: a vessel for containing a quantity of water, wherein the water contains micro-organisms, said vessel including an inlet valve for admitting water into said vessel; an oven for containing said vessel and heating said water to a temperature, and for a duration, sufficient to at least substantially remove said micro-organisms and to generate a substantially micro-organism free steam; a vapor outlet conduit for channeling said substantially micro-organism free steam into said airflow conduit to humidify said air flowing through said airflow conduit; and a controller for controlling said drain valve and said inlet valve, and for turning on and off said microwave oven, said controller further controlling said drain valve such that an entire quantity of heated water is drained from said vessel before said controller causes said inlet valve to admit a fresh quantity of water into said vessel.
 2. (canceled).
 3. The system of claim 1, wherein said oven comprises a microwave oven.
 4. The system of claim 1, further comprising a water drain line in communication with said vessel for allowing said quantity of water to be drained from said vessel, said water drain line housing said drain valve.
 5. The system of claim 4, further comprising a vacuum accumulator in communication with said water drain line for assisting in withdrawing said quantity of water from said vessel through said water drain line, and at least temporarily containing said quantity of water.
 6. The system of claim 1, further comprising a water supply conduit in communication with said vessel for supplying said quantity of water to said vessel.
 7. (canceled).
 8. (canceled).
 9. The system of claim 1, further comprising a humidity sensor in communication with the vapor outlet conduit for detecting a level of humidity in said air flowing in said airflow conduit.
 10. The system of claim 1, further comprising a vapor injection nozzle for receiving said substantially micro-organism free steam from said vapor outlet conduit and dispersing same into said air flowing through said airflow conduit.
 11. The system of claim 10, wherein said vapor injection nozzle comprises: a plurality of vanes, said vanes being subject to said air flowing through said airflow conduit such that said vanes cause said air flowing in said airflow conduit to swirl to thus help in dispersing and intermixing said substantially micro-organism free steam with said air.
 12. The system of claim 1, further comprising a water overflow conduit in communication with said vessel for receiving any of said water contained in said vessel that overflows from said vessel during heating of said water by said oven.
 13. The system of claim 1, wherein said water overflow conduit includes a pressure relief valve for allowing a flow of said water through said water overflow conduit only when a predetermined pressure is reached in said water overflow conduit.
 14. The system of claim 1, further comprising: a pressure regulating valve disposed in said airflow conduit for regulating a flow of said steam into said airflow conduit and maintaining a pressure of said steam at a pressure present in said airflow conduit.
 15. A system for humidifying air being supplied within a confined area, said system comprising: an airflow conduit for providing a flow of air into said confined area; a vessel for containing a quantity of water, wherein the water contains micro-organisms; an oven for heating said water in said vessel to a temperature, and for a duration, sufficient to at least substantially remove said micro-organisms and to generate a substantially micro-organism free steam; a vapor injection system for injecting said substantially micro-organism free steam into said airflow conduit and assisting in mixing said substantially micro-organism free steam with said air flowing through said airflow conduit to humidify said air; and a controller for draining an entire quantity of heated water within said vessel after a heating cycle before causing a fresh quantity of water to be admitted into said vessel.
 16. (canceled).
 17. The system of claim 15, wherein said oven comprises a microwave oven.
 18. The system of claim 15, further comprising a water supply conduit for supplying said quantity of water to said vessel.
 19. The system of 18, further comprising: a valve disposed in said water supply conduit; and a wherein said controller controls said valve to admit only said quantity of water into said vessel, said quantity representing a volume of water sufficient to fill said vessel to a desired level.
 20. The system of claim 15, further comprising a water drain conduit for draining water from said vessel.
 21. The system of claim 20, further comprising a valve disposed in said water drain conduit for controlling a draining of water from said vessel.
 22. (canceled).
 23. The system of claim 15, further comprising a water overflow conduit in communication with said vessel for draining water that rises above a predetermined level in said vessel, from said vessel.
 24. The system of claim 15, further comprising a humidity sensor for sensing a level of humidity in said air flowing in said airflow conduit.
 25. The system of claim 15, further comprising a water level sensor for sensing a level of water in said vessel.
 26. The system of claim 15, further comprising a vacuum accumulator in communication with said vessel for assisting in draining said water from said vessel after said water has been heated for a predetermined time.
 27. The system of claim 15, wherein said vapor injection system comprises: a vapor outflow conduit in communication with said vessel; and a plurality of vanes disposed in a path of said air flowing through said airflow conduit to cause a swirling of said air flowing in said airflow conduit to assist in dispersing said substantially micro-organism free steam into said air.
 28. The system of claim 15, further comprising; a pressure regulator valve for regulating a pressure of said steam entering said airflow conduit.
 29. (canceled)
 30. (canceled)
 31. (canceled)
 32. (canceled)
 33. (canceled)
 34. (canceled)
 35. (canceled)
 36. (canceled)
 37. (canceled) 